Deep saline aquifers and depleted carbonate reservoirs are generally considered promising locations for subsurface CO₂ storage. However, carbonate minerals particularly calcite can react with CO₂-saturated brine, resulting in dissolution of carbonate and potentially mechanical compaction. Thus, it is crucial to understand the extent of this reaction in both water-wet and oil-wet scenarios, and subsequently its consequences on CO₂ storage in depleted carbonate reservoirs. In this study, medical X-ray computed tomography (CT) was used to image water-wet and oil-wet Indiana limestone core samples before and after CO₂ flooding. Changes in the rock matrix and pore structure were further assessed from the porosity and permeability data computed from the CT images. In both cases, imaging shows a significant amount of dissolution resulting in an increase in pore volume after core flooding with live brine and subsequently CO₂. This increase in porosity is 46.7% and 19% for the water-wet and oil-wet core, respectively. Likewise, the brine permeability for the water-wet core increased from 9.2 mD (before CO₂ flooding) to 108 mD (after CO₂ flooding), whereas the permeability for the oil-wet core increased modestly from 9.0 mD to 20.1 mD. These results suggests that the reactivity is less pronounced in the oil-wet rock compared to the water-wet rock. Therefore, the wettability state of a target carbonate reservoir and the subsequent potential for the wettability state to be modified should be considered when assessing the CO₂ storage capacity and integrity.

深含盐含水层和枯竭的碳酸盐储层通常被认为是地下CO ₂储存的有希望的位置。然而，碳酸盐矿物特别是方解石可以与CO ₂饱和盐水反应，导致碳酸盐溶解和潜在的机械压实。因此，了解该反应在水湿和油湿情况下的程度以及随后对枯竭碳酸盐储层中 CO ₂储存的影响至关重要。_{在这项研究中，医学 X 射线计算机断层扫描 (CT) 用于对 CO 2}驱前后的水湿和油湿印第安纳石灰岩岩心样品进行成像。岩石基质的变化从 CT 图像计算的孔隙度和渗透率数据进一步评估孔隙结构。在这两种情况下，成像显示大量溶解导致在用活盐水和随后的 CO ₂驱替岩心后孔隙体积增加。亲水岩心和亲油岩心的孔隙率分别增加了 46.7% 和 19%。同样，亲水岩心的盐水渗透率从 9.2 mD（CO ₂驱前）增加到 108 mD（CO _2后）驱），而亲油岩心的渗透率从 9.0 mD 适度增加至 20.1 mD。这些结果表明，与亲水岩石相比，亲油岩石中的反应性不太明显。_{因此，在评估CO 2}储存能力和完整性时，应考虑目标碳酸盐储层的润湿性状态以及随后改变润湿性状态的可能性。